Rendering a wall is a skillful craft that transforms the exterior aesthetics of your property while providing additional protection against the elements. Whether you're looking to refresh the facade of your home or simply want to add an extra layer of insulation, understanding the process of rendering is crucial.
Rendering is the process of applying a mixture typically made of sand cement and lime to the exterior walls of a building. It can be used on a variety of surfacesfrom brick to stone and even on interior walls. The render not only improves the appearance of your property but also helps in waterproofing and insulating your walls.
Before diving into the process, it's important to understand the types of render available:
Proper preparation is key to a successful render. Here’s how to prepare your wall:
The most common mix for a standard render is a 1:1:6 ratio of cement, lime, and sand. However, the exact mix can vary depending on the type of render you choose.
Apply the first coat of render using a trowel. This layer should be about 5mm thick. Once applied, use a scratch comb to create a rough surface which helps the next layer to adhere.
After the first coat has dried (usually after a few days), apply the second coat. This should be thicker, around 5-15mm.
The final layer is the decorative surface. It can be smoothed, textured, or patterned depending on your preference.
Allow the render to cure slowly, avoiding direct sunlight and extremes of temperature to prevent cracking.
Once the render is cured, it's time for any finishing touches:
Rendered walls typically require little maintenance, but occasional cleaning and checking for cracks or damage is recommended.
Rendering a wall can be a rewarding DIY project. By following the right procedures and using the correct materials you can achieve a durable and attractive finish that will protect and enhance your property for years.
The ideal time is during mild weather conditions, typically in the late spring or early autumn, to avoid the render drying too quickly or being damaged by frost.
It can take anywhere from a few days to a week for each coat to dry. It's essential to let each layer dry completely before applying the next.
It's not recommended to render over old paint. Existing render needs to be stable and sound; if it's not, it should be removed before applying new render.
The total thickness usually ranges from 15mm to 20mm, applied over two or three coats.
Yes, a primer can improve the adherence of the render, especially on smooth or non-porous surfaces.
Rendering can be applied to most types of walls, but the method and materials may vary depending on the wall's substrate.
For certain substrates or to reinforce the render and prevent cracking, using a fiberglass mesh can be beneficial.
Use a float to smooth the render during the final coat. The key is to achieve the right consistency with your mix and apply evenly.
Plastering is typically done on interior walls with a finer mix, while rendering is for exterior walls with a coarser mix to withstand weather conditions.
Yes, you can add pigments to the mix for a colored render or paint the render once it's cured.
Small cracks can be filled with an appropriate filler, while larger ones may require cutting out and re-rendering the affected area.
Dampen the wall slightly with water, avoid rendering in direct sunlight, and consider using additives that slow down the drying process.
It's not advisable to render in the rain as it can wash out the cement and weaken the render.
